Aramark is asking its workers to buy health insurance in a new way. The Philadelphia food service giant joins a growing list of large companies — especially those with lots of part time employees — that are using a corporate or "private" exchange to link workers to coverage.

 Last week, WHYY/NewsWorks reported that the region's biggest health insurance company, Independence Blue Cross, is offering health plans on the country's largest private exchange, AON Hewitt. Now we know, that Aramark is among the companies that will use AON Hewitt's corporate exchange.

Jill Malila, vice president, global benefits plan design and finance, said all Aramark employees who qualify for health coverage will get their coverage through the private exchange. She declined to give an exact number, but said "tens of thousands" of Aramark workers are in the company's health plans now.

When companies shutter their in-house benefits departments and move workers to a private exchange, often they boast about the increased number of plan options available. For Aramark, Malila said the number of plans stays the same — at four — but she said workers will have "greater choice."

A new online tool makes comparison-shopping easier to do, she said.

"They'll have tools to calculate the potential medical expenses they'll incur throughout the year," Malila said. "Then they can select a healthcare plan.  They can look at based on price, they can look at based on name brand of the insurance company, they can select that carrier based on whether or not their doctors and hospitals are in the carrier network."

"From the administrative perspective, it does alleviate some of the burden that employers have when they are trying to manage multiple carriers," Malila said.

Disclosure: L. Frederick Sutherland, who is executive vice president and chief financial officer of Aramark Corp., is also chair of WHYY's board of directors.